Turn off the prompt that appears when you use a certificate or PGP key
that is not recommended for use
1.
On the home screen or in a folder, click the Options icon.
2.
Click Security > S/MIME or PGP.
3.
In the General section, clear the Warn About Problems With My Certificates checkbox or Warn About Problems
With My PGP Keys checkbox.
4.
Press the
key > Save.